Hook



FIG. 1 is a perspective view showing the new design for a hook;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a left view thereof, the right side view being a mirror image of the left side view shown;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view thereof. 

The ornamental design for a hook, as shown and described. 